Re: urgnet need for complete C# code for Password encryption/decryption

From: Dejan Sarka (dejan_please_reply_to_newsgroups.sarka_at_avtenta.si)
Date: 05/17/03 

Date: Sat, 17 May 2003 16:10:29 +0200

I agree - hashing is becoming nearly a standard. 

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"Amir Eshterayeh" <aeshterayeh@hotmail.com> wrote in message
news:uqSkZxDHDHA.1828@TK2MSFTNGP10.phx.gbl...
> Thank you so much. I have found the following information from
>
> http://www.dotnet247.com/247reference/msgs/1/8366.aspx
>
> which is said it is better to user hashing instead of encryption for
> password coding.
>
> I will be happy to know your idea cause I need to apply it today :)
>
> Best Regards
> Amir Eshterayeh
> ----------------------------------------------------
>
> Phillip Pratt [@interact.com]
> What you are talking about is hashing, not encrypting. A hash algorithm
> is a
> one-way function (There's no way to get the original back from the
> hash), an
> encryption algorithm is a two-way function. Other than that distinction,
> though what you are doing is the way to go. A hash is the appropriate
> method
> for storing passwords because there is never a reason to get back the
> original. Also with a hash function, the output size is predetermined
> and
> independent of the input size (20 Bytes in the case of SHA1). This makes
> choosing a datatype in a database pretty easy. And as far as hashing
> algorithms go, SHA1 is a good one.
>
> Here's an example using a text box to get the input value:
>
> UnicodeEncoding enc = new UnicodeEncoding();
>
> byte[] plainbytes = enc.GetBytes(textBox1.Text);
>
> SHA1 sha = new SHA1CryptoServiceProvider();
>
> byte[] result = sha.ComputeHash(plainbytes);
>
> You may want to then encode the result byte array to some sort of text
> encoding (Base64 perhaps?) or just leave it as a byte array for storage.
>
> Hope this helps.
>
> "Harris Boyce III" <hboyce@thedotworks.com> wrote in message
> news:#bqayu7TBHA.1860@tkmsftngp05...
> [Original message clipped]
>
> *** Sent via Developersdex http://www.developersdex.com ***
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